Hi! Time to share my (little) experience about the FIA mode (manufacturer and nations). IMO, it's a good mix of serious racing and fun, as long as your opponents are fair-play. I really like the qualifying system, that we all have 8 mins to do a time. Sadly, this mode could be better if not everyone was that close at the beginning. But overall, the races are really enjoyable and long enough.
The biggest fights I've had was in Kyoto and Blue Moon (Nations Cup). In Kyoto it was really fair-play since the guy behind me (I don't remember his name) was using his headlights to prevent me from an attack, which was really enjoyable. I started and finished 3rd with 1182 points. On Blue Moon, with the NASCAR-like race, I've fallen down to 10th position (starting from pole position) and I made my way through to 3rd place (1287 points), an unexpected result. I tried to avoid every contact during that race, but it was too hard, at least I didn't make someone spin or something which is an achievement in that kind of race.
On the other hand, the races in Manufacturer Cup were much calmer since it was basically Pole Position and win, and it's even more stressful when you know that if you lose the race, it's your only fault. At least, I've won much points (1477 and 1433 points).
On a sad note, I feel like a good part of drivers are using the "counter-steering assistance". I don't know if it helps, but it's not something I really like.
In few words (IMO again), this FIA mode is like the daily races with faster drivers, rankings, and faster drivers, I like it
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